This invention relates to a portable electronic memorandum device comprising a data memory which can electronically read/write character data items such as telephone numbers, addresses, schedules and the like.
Modern electronic watches and small electronic calculators can store character data items such as names, telephone numbers, addresses, schedules, and the like by means of a data input means from a keyboard in addition to its original function. A desired character data item can be read out for display.
For example, a device disclosed in U.S. Pat. No. 3,999,050 has a keyboard consisting of letter, numerial, and function keys and stores a name, a telephone number and a time to call in a data memory by means of the above keys. When it is the time to make a predetermined call, the name and telephone number to call are displayed on a display unit.
Another prior art device disclosed in U.S. Pat. No. 4,117,542 comprises a keyboard consisting of keys for designating letters, numerals and functions, and stores telephone numbers, street addresses, appointments, an agenda and the like in a data memory means. When letters representing a desired name are keyed in, the telephone number and the address of the corresponding person are read out from the data memory means so as to display them on a display unit.
In these prior art devices, the data is written/read from the data memory by operation of the keys on the keyboard, resulting in a complex input/output circuit configuration. Therefore, it is difficult to apply these techniques to small electronic equipment, such as wristwatches.